Condition Analysis
AI-powered assessment using site data and 14-day weather history
The rock is thoroughly saturated after a prolonged wet spell — 29mm in the last 7 days alone, with today adding a further 12.2mm of heavy rain. There has been no meaningful drying window; the gritstone will be deeply wet internally and climbing today or in the near future risks permanent damage to holds and routes.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and lower walls tend to accumulate runoff from the moorland above, and seepage can persist for days after heavy rain even when upper faces appear dry.
- The exposed S/SW aspect and moorland wind normally aid drying significantly, but the relentless rainfall since early June (72mm in 28 days) has kept the rock saturated well beyond what wind and sun can offset.
- Open moorland at 260m means cooler temperatures than valley crags — average just 12.2°C over the last week — which further slows evaporation from the porous gritstone.
- Popular lower-grade problems on the Calf see heavy traffic; climbing on weakened wet gritstone risks accelerated erosion and hold breakage on these well-loved classics.
Warnings
3
- Climbing on saturated gritstone causes irreversible hold breakage and route damage — the rock may feel gritty or crumbly underfoot even where the surface looks dry.
- The prolonged wet period means internal moisture levels are extremely high; surface drying will be misleading — do not trust appearance alone.
- Further rain is forecast every day through June 21st, preventing meaningful recovery.
Reasoning
The gritstone is deeply saturated: 29mm fell in the last 7 days with rain on most days, today alone delivered 12.2mm in heavy bursts, and 72mm has fallen over the past 28 days with almost no sustained dry periods.
Despite the exposed S/SW aspect and moderate winds, there has been no consecutive dry period longer than about 2 days since early June, and humidity has averaged 81% — far too little drying time to meaningfully reduce internal moisture in porous gritstone.
With prolonged saturation, compressive strength loss of 30–50% is likely; climbing risks hold breakage and accelerated grain loosening on this heavily used crag.
Early summer should offer good drying conditions, but this June has been unusually wet and cool, with temperatures well below seasonal norms and persistent high humidity preventing the rock from recovering.
Contributing Factors
6
12.2mm of rain fell today, including 8mm+ in a two-hour burst overnight, thoroughly re-wetting the entire crag.
Rain has fallen on the majority of days since June 1st, totalling 72mm over 28 days with no meaningful drying window.
Humidity has averaged 81% over the last week and reached 90% today, severely limiting evaporative drying.
Average temperature of just 12.2°C over the last week is well below summer norms and slows drying significantly.
The exposed moorland setting and southerly aspect will aid drying once rain stops, but cannot overcome the current degree of saturation.
The 5-day forecast shows rain every day (0.3–7.0mm), preventing any sustained drying period from developing.
Recommendations
3
- Do not climb at Cow and Calf today or in the coming days — the gritstone is deeply saturated and needs a sustained dry spell of at least 48–72 hours to begin recovering.
- Monitor conditions for a window after June 22nd, which is forecast dry, but will likely still need additional dry days given the prolonged saturation.
- If visiting anyway, check the ground at the base of the crag — if the peat and soil are wet underfoot, the rock is certainly still too wet to climb on safely.
Previous Analyses
Do Not Climb
80%
2 days ago
Despite a brief dry window on June 13–14, the preceding two weeks have delivered over 60mm of rain across numerous wet days, leaving the gritstone deeply saturated internally. Today's trace precipitation and tomorrow's forecast 5.3mm continue to prevent any meaningful drying, and conditions are not suitable for climbing.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and main crag face S/SW and are exposed to wind, which helps surface drying, but the prolonged saturation from the last two weeks means internal moisture will persist far longer than surface appearance suggests.
- Ilkley Moor's open moorland setting means the base of the crag and lower boulder problems can retain seepage and ground moisture long after the upper faces appear dry — check the soil at the crag base as a proxy for rock moisture.
- At 260m altitude, overnight temperatures are dropping to 7–9°C which significantly slows evaporation rates compared to lowland venues.
- The popular Calf boulder has a mix of overhanging and vertical faces — overhangs may feel dry to the touch sooner, but the rock mass itself will still be weakened internally after this extended wet spell.
Warnings
2
- Climbing on saturated gritstone causes permanent hold breakage and route damage — Ilkley is an irreplaceable venue and the community ethic is clear: do not climb on wet grit.
- The rock surface may appear dry while the interior remains dangerously weakened — do not be fooled by a dry-looking surface after only 1–2 days.
Reasoning
Over 60mm of rain in the last 28 days — with 21.5mm in the last 7 days spread across multiple events (June 8–12 being particularly wet) — means the gritstone is deeply saturated internally despite brief surface drying on June 13–14.
Only about 1.5 genuinely dry days (June 13–14) have elapsed since the last significant rain on June 12, and today's 0.3mm trace rain plus high humidity (77%) interrupt that drying; even with the S/SW aspect and exposed wind, this is nowhere near the 48–72+ hours of proper drying needed after heavy cumulative rainfall.
With the rock mass likely well above the critical 1% saturation threshold after prolonged wetting, compressive strength is significantly reduced and climbing risks hold breakage and accelerated erosion on this heavily trafficked gritstone venue.
Early June temperatures of 13–16°C and humidity averaging 79% over the past week provide only moderate evaporative potential, and the sustained unsettled pattern is typical of a poor early-summer spell in northern England.
Contributing Factors
6
Over 60mm in 28 days with 21.5mm in the last 7 days across multiple rain events has deeply saturated the porous gritstone.
Only 1.5 dry days since the last significant rain on June 12, far short of the 48–72+ hours needed after heavy cumulative wetting.
Average humidity of 79% over the past week severely limits evaporative drying even when it is not raining.
The south/south-west facing, wind-exposed position provides above-average drying potential when dry weather does arrive.
Small amounts of rain today (0.3mm total) and overcast skies reset any drying progress from June 13–14.
5.3mm forecast for June 16 will re-wet the rock and further delay any meaningful drying window.
Recommendations
3
- Do not climb today — the gritstone is almost certainly still wet internally despite any surface drying from the brief dry spell on June 13–14.
- Monitor the forecast closely; a sustained dry window of at least 48–72 hours with low humidity and wind is needed before conditions will be suitable after this prolonged wet period.
- If visiting, check the soil and vegetation at the base of the crag — if the ground is damp, the rock is certainly too wet to climb safely.
Do Not Climb
30%
3 days ago
The rock at Cow and Calf is almost certainly still saturated internally after a prolonged wet spell that deposited over 26mm in the last 7 days alone, with rain on 8 of the last 10 days. Only one full dry day (today) has elapsed since the last significant rain, which is far too little drying time for porous gritstone that has been repeatedly soaked over two weeks.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and lower buttresses tend to hold seepage at their bases after prolonged wet periods, and the moorland setting means groundwater remains high for days after sustained rain.
- Despite the favourable S/SW aspect and exposed position, two weeks of near-continuous rain with high humidity (averaging 80%) will have deeply saturated the gritstone well beyond what surface drying can address in one day.
- The open moorland around the crag can appear deceptively dry on a sunny day, but peat and heather at the base will retain moisture — check the ground at the foot of the rock as a proxy for internal dampness.
- Popular lower problems on the Calf boulder and the base of the main crag will be the last areas to dry and should be avoided longest.
Warnings
2
- Gritstone that appears surface-dry after one day can still be deeply saturated internally — climbing risks permanent hold breakage and route damage.
- The forecast shows further light rain on each of the next four days, which will repeatedly re-wet the rock and prevent meaningful drying progress.
Reasoning
With 26.4mm in the last 7 days spread across 8 rain days, and nearly 60mm over the last 28 days, the gritstone will be deeply saturated internally — likely well above the critical 1% saturation threshold where significant weakening begins.
Only one dry day has passed since the last rain (2.7mm on June 12, trace on June 13), and despite the south-facing exposed aspect and moderate wind, a single day cannot adequately dry gritstone that has been repeatedly wetted over a two-week period with high ambient humidity averaging 80%.
The prolonged saturation significantly increases the risk of hold breakage and grain loosening — gritstone can lose 10–50% of its compressive strength when wet, and the cumulative wetting has penetrated deep into the rock matrix.
Early June temperatures are moderate (11–17°C) but not high enough to drive rapid evaporation, and the persistent high humidity (73–92%) severely limits the drying rate even during the longest days of the year.
Contributing Factors
7
Rain fell on 8 of the last 10 days totalling over 26mm, deeply saturating the porous gritstone well beyond surface level.
A single day of drying is wholly insufficient after two weeks of repeated wetting — guidelines call for 48–72+ hours minimum after heavy rain.
Average humidity of 80% over the last week severely limits evaporative drying, even with wind exposure.
The S/SW aspect and exposed hilltop position provide the best possible drying conditions for the site, somewhat accelerating surface drying.
Wind speeds of 20–35 km/h over recent days help move moist air from the rock surface, aiding drying.
Average temperatures around 12°C are moderate and do not drive fast evaporation compared to warmer summer conditions.
Light precipitation forecast for June 15–18 will repeatedly re-wet the surface and reset drying progress before the rock can properly dry out.
Recommendations
3
- Do not climb today — the rock has had only one dry day after two weeks of persistent rain and remains dangerously saturated internally despite any surface drying.
- Wait for a sustained dry spell of at least 3–4 consecutive dry days with lower humidity before visiting; the forecast does not show this window arriving until June 19–20 at the earliest.
- When you do visit, check the ground at the base of the crag and feel for dampness on lower holds — if the peat or soil is moist, the rock is almost certainly still wet inside.
Do Not Climb
90%
4 days ago
The rock at Ilkley is almost certainly saturated after a prolonged wet spell delivering nearly 28mm in the last 7 days with no consecutive dry days. Despite the exposed, south-facing aspect, the persistent rain, high humidity, and cool temperatures mean the gritstone has had no opportunity to dry out internally.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and main crag faces are south/south-west facing and exposed, which will help them dry faster than sheltered or north-facing gritstone venues once a dry spell arrives.
- The open moorland setting means the base of the crag and surrounding ground will be waterlogged after this prolonged wet period — check ground moisture as a proxy for rock condition.
- Seepage can persist on the main Cow buttress and around cracks on the Calf boulder for days after prolonged rain, even when face sections appear surface-dry.
- At 260m altitude, temperatures have been notably cool (averaging ~12°C) which significantly slows evaporative drying despite the wind exposure.
Warnings
2
- Climbing on saturated gritstone causes permanent hold breakage and irreversible route damage — Ilkley is a heavily used venue where this damage would be significant.
- The rock surface may appear dry before the interior has dried — do not be deceived by surface appearance after such prolonged saturation.
Reasoning
The rock is almost certainly saturated throughout, having received rain on 9 of the last 10 days totalling ~28mm, with today recording another 0.6mm and humidity averaging 80%.
Despite the exposed S/SW aspect and strong westerly winds (20–36 km/h), there have been zero consecutive dry days and persistent high humidity (76–92%), meaning no meaningful drying has occurred.
Gritstone at this saturation level will have lost 30–50% of its compressive strength; climbing now risks permanent hold breakage and accelerated erosion on this heavily-used venue.
Early June should offer improving conditions, but this has been an unusually wet and cool spell; temperatures around 12–14°C combined with high humidity dramatically slow drying rates.
Contributing Factors
6
Nearly 28mm of rain over the last 7 days across 9 of 10 wet days has left the gritstone deeply saturated with no drying window.
Today still recorded 0.6mm of precipitation, meaning there has been no unbroken dry period to begin meaningful drying.
Humidity has averaged 80% over the past week with peaks of 92%, severely limiting evaporative drying even in wind.
Average temperatures of ~12°C over the last week are well below summer norms, reducing the rate of evaporation from the rock.
Sustained winds of 20–36 km/h on the exposed moorland will aid surface drying once precipitation ceases.
The favourable aspect will maximise solar drying once dry weather establishes, but has been negated by persistent cloud and rain.
Recommendations
3
- Do not climb today — the gritstone is saturated and structurally weakened after over a week of near-continuous rain.
- Wait for at least 48 hours of completely dry weather with humidity below 70% before considering a visit; given the cumulative saturation, 72+ hours would be more appropriate.
- If visiting in the next few days, check the ground at the base of the crag — if the moorland turf and soil are still damp, the rock will be too.
Do Not Climb
92%
5 days ago
Ilkley Cow and Calf has received 33mm of rain in the last 7 days across almost daily showers, including 10.9mm yesterday and 2.4mm today, with no meaningful drying window. The gritstone will be thoroughly saturated internally despite the exposed, south-facing aspect, and needs several consecutive dry days before climbing is appropriate.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks are large masses of gritstone that absorb and retain moisture deep into the rock body — after prolonged wet spells, the interior can remain saturated long after the surface appears dry.
- The south/south-west aspect and exposed moorland position give this crag above-average drying potential, but the sustained wet period (rain on 10 of the last 12 days) has overwhelmed any drying advantage.
- Lower sections of the Calf boulder and north-facing arêtes/walls will retain moisture significantly longer than the sun-catching upper faces.
- Open moorland drainage means the ground at the crag base is a useful moisture indicator — if the peat and grass are still soggy, the rock is certainly still wet inside.
Warnings
2
- The gritstone has been repeatedly saturated over nearly two weeks — surface dryness will NOT indicate internal dryness; do not trust a dry-looking surface.
- Hold breakage risk is significantly elevated; climbing now risks permanent, irreversible damage to routes and boulder problems at this popular venue.
Reasoning
With 33mm over the past 7 days falling on 10 of the last 12 days — including 10.9mm yesterday and 2.4mm today — the gritstone is almost certainly at or near full saturation, well above the critical thresholds for strength loss.
Despite the exposed position and SW aspect, there has been no consecutive dry window of more than a few hours in over 10 days; strong westerly winds today (35 km/h) will help surface drying but cannot address deep internal saturation accumulated over nearly two weeks of repeated wetting.
At near-full saturation, gritstone holds are at serious risk of breakage — compressive strength reductions of 30%+ are expected, and repeated wet-climbing accelerates irreversible erosion of this heavily-trafficked venue.
Early June temperatures (12–17°C) are moderate but the prolonged unsettled weather pattern with high humidity (82% average) is significantly retarding evaporation and drying rates.
Contributing Factors
6
Rain fell on 10 of the last 12 days totalling 33mm in the last week alone, with no meaningful drying window to reduce internal saturation.
Fresh precipitation today means the zero-day dry count resets and the rock surface is currently wet.
Sustained humidity above 80% over the past week severely limits evaporative drying even when it is not actively raining.
Today's 35 km/h westerly winds and the exposed moorland position will aid surface evaporation once rain stops.
The favourable aspect provides good solar heating which will help once a dry spell establishes, but has been insufficient during the current wet period.
Temperatures are adequate for drying but not exceptional; they are not accelerating evaporation enough to counteract the high humidity and frequent rain.
Recommendations
3
- Do not climb today or tomorrow — wait for at least 48–72 hours of dry, breezy weather before considering a visit.
- Check the ground conditions at the base of the Calf boulder on arrival: if peat and grass are damp, the rock is certainly still wet inside.
- Monitor the forecast from June 14 onwards — if the predicted dry spell materialises with moderate wind, conditions may begin to improve by June 15–16, but assess visually before climbing.
Do Not Climb
95%
6 days ago
The gritstone at Cow and Calf is thoroughly saturated after nearly two weeks of repeated rainfall totalling over 50mm, with heavy rain still falling today and humidity above 90%. Even with the favourable S/SW aspect and exposed position, the rock will need several consecutive dry days before it is safe to climb.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks receive rain from all angles due to their freestanding, exposed nature — meaning all faces get wetted during prolonged rain events, not just the windward side.
- The south/south-west aspect and exposed moorland position are significant advantages for drying once dry weather arrives, often allowing Cow and Calf to dry faster than more sheltered gritstone venues.
- Seepage can persist on the main crag faces and at the base of the Calf boulder after prolonged wet spells, particularly where cracks and horizontal breaks channel water.
- At 260m on open moorland, mist and low cloud can keep humidity near saturation even on nominally dry days, slowing surface evaporation despite wind.
Warnings
2
- Climbing on saturated gritstone causes permanent, irreversible damage to holds and route surfaces — please wait for conditions to improve.
- After this prolonged wet spell, the rock surface may appear dry before the interior has dried sufficiently; do not be misled by a dry-looking surface.
Reasoning
The rock is almost certainly saturated throughout after 10 consecutive days of rain (June 1–11) delivering nearly 54mm cumulatively, with today alone adding 7.7mm at 91% humidity.
There has been no meaningful drying window in over a week; despite good wind speeds (20–30 km/h), persistent rain and humidity above 78% have prevented any net evaporation from the rock.
Gritstone at this level of saturation will have lost 30–50% of its compressive strength, making hold breakage and surface erosion a serious risk — climbing now would cause permanent damage to routes.
Early June should offer good drying potential, but this has been an unusually wet spell; temperatures have been cool for the season (averaging only 11.4°C over the past week), further slowing any drying.
Contributing Factors
7
Ten consecutive days of rain from June 1–11 have deposited nearly 54mm, keeping the rock continuously wetted with no drying opportunity.
Today's forecast shows intermittent rain throughout the day totalling 7.7mm, with 100% cloud cover and humidity 90–97%, ensuring the rock remains fully saturated.
Average humidity over the past week has been 81%, and today reaches 91–97%, effectively preventing any evaporation from the rock surface.
Temperatures have averaged only 11.4°C over the past week, well below seasonal norms, reducing evaporative drying potential.
Sustained winds of 20–31 km/h at this exposed site will significantly aid drying once the rain stops and humidity drops.
The S/SW aspect will receive good solar radiation once skies clear, accelerating surface and near-surface drying.
From June 14 onwards the forecast shows zero precipitation, declining humidity to 55%, and warming temperatures to 22°C — excellent drying conditions.
Recommendations
3
- Do not climb today or in the next two days — the rock is deeply saturated and needs an extended dry spell to recover.
- Target June 15 or 16 as the earliest realistic window, but visually inspect the rock on arrival, checking that the base of the crag and crack systems are fully dry.
- Use the 'ground test': if the soil and peat at the base of the boulders is still damp, the rock interior is almost certainly still holding moisture.
Do Not Climb
95%
8 days ago
The rock is thoroughly saturated after a prolonged wet spell — over 32mm in the last 7 days with rain on almost every day, including 9.3mm today. Despite the exposed, south-facing aspect, there has been no meaningful drying window and the gritstone will be deeply wet internally; climbing today or in the next couple of days would risk permanent hold damage.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks are exposed to wind on all sides, which aids surface drying, but the persistent rain and high humidity (81% average over 7 days) have prevented any real drying progress.
- Ilkley Moor's open aspect means seepage is less of a problem than at sheltered crags, but the cumulative 47.8mm over 28 days with the heaviest falls in the last week means deep saturation is likely throughout.
- Lower sections of the Calf boulder and north-facing facets of individual blocks will retain moisture longest and should be the last areas considered climbable.
- The crag's popularity means any hold damage from wet climbing would affect a large number of climbers — extra caution is warranted at a venue of this significance.
Warnings
2
- Climbing on saturated gritstone risks permanent hold breakage — the rock may have lost 30–50% of its compressive strength at current moisture levels.
- The surface may appear dry before the interior has dried — do not be deceived by wind-dried surfaces after such a prolonged wet spell.
Reasoning
With rain falling on 7 of the last 8 days totalling over 32mm, plus 9.3mm today, the gritstone is deeply saturated well beyond the critical 1% threshold where significant strength loss begins.
Despite the south/south-west aspect and exposed position with strong winds (20–33 km/h), the continuous rainfall and high humidity (78–86%) have allowed no meaningful drying period — each shower re-wets the rock before any progress can be made.
At current saturation levels, compressive strength is likely reduced by 30%+ and climbing poses a serious risk of hold breakage and permanent grain loosening on these well-trafficked gritstone problems and routes.
Early June temperatures (12–15°C) are moderate but not warm enough to drive rapid evaporation, and the unsettled Atlantic weather pattern is delivering repeated fronts that prevent drying.
Contributing Factors
7
Over 32mm in the last 7 days with rain on nearly every day ensures deep saturation of the porous gritstone.
Significant rain today with showers throughout the day resets any drying clock completely.
Average humidity of 81% over the past week severely limits evaporative drying even between rain events.
Sustained winds of 20–33 km/h help move moist air from the rock surface, which will aid drying once rain stops.
The favourable aspect and open moorland position will accelerate drying once a dry spell establishes, but this advantage is currently negated by continuous rain.
Further rain is forecast on June 10 (7.4mm), 11 (3.9mm), and 12 (1.5mm), extending the wet period before any drying window opens.
Temperatures of 12–15°C are below ideal for rapid drying and slow the evaporation process.
Recommendations
3
- Do not climb today or in the next few days — the gritstone is deeply saturated and needs a sustained dry spell before it will be safe.
- Monitor conditions from June 13 onwards; if the forecast dry spell materialises, the earliest realistic window for assessment would be June 14–15 given the exposed, south-facing aspect and wind.
- When you do visit, check the ground at the base of the boulders — if the soil and peat are still damp, the rock almost certainly is too.
Do Not Climb
90%
9 days ago
The rock is almost certainly saturated after a prolonged wet spell totalling ~35mm over the past week, with rain continuing through this morning. Despite an afternoon drying window today, the gritstone will not have had anywhere near enough time to dry internally, and heavy rain (11.4mm) is forecast again tomorrow.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and many problems at Cow and Calf sit on open moorland with excellent wind exposure, which helps surface drying but cannot compensate for deep saturation after a week of repeated wetting.
- The base areas around the Calf boulder and lower walls tend to stay damp longer due to drainage from the moor above and pooling at the foot of boulders.
- The S/SW aspect is favourable for solar drying in summer, but persistent cloud cover and cool temperatures (13–16°C) over recent days have significantly limited solar gain.
- The prolonged wet period from June 1–8 (~35mm cumulative) means the gritstone is likely saturated well beyond the surface — internal moisture will persist for days even after rain stops.
Warnings
2
- Climbing on saturated gritstone risks permanent hold breakage and irreversible route damage — the rock may appear surface-dry while remaining dangerously weak internally.
- The wet spell is ongoing with more heavy rain forecast tomorrow; do not be tempted by the brief dry afternoon window today.
Reasoning
With ~35mm of rain over the past 7 days falling in repeated pulses (never more than one consecutive dry day), the porous gritstone is almost certainly deeply saturated, well above the critical ~1% threshold where significant weakening begins.
Although the S/SW aspect and exposed position normally aid drying, the last meaningful rain was only hours ago this morning, and the rock has had no sustained dry period — surface drying this afternoon is cosmetic and does not address internal moisture.
At current saturation levels, compressive strength is likely reduced by 30%+ and hold breakage risk is high; climbing now risks permanent damage to routes on this popular and irreplaceable venue.
Early June temperatures are moderate (13–15°C) but well below the recent warm spell, and humidity has averaged 81% over the past week, substantially slowing evaporation rates.
Contributing Factors
6
Approximately 35mm has fallen over the past 7 days in repeated pulses with no meaningful drying window, leaving the gritstone deeply saturated.
Over 6mm of rain fell through this morning, re-wetting any marginal surface drying from yesterday.
11.4mm is forecast for June 9, which will re-saturate any surface drying achieved this afternoon and extend the wet period further.
Humidity has averaged 81% over the past week, severely limiting evaporative drying potential.
The south-facing exposed position is the best possible configuration for drying once dry weather eventually arrives.
Winds of 20–30 km/h are helping move moist air from the rock surface, which will aid drying once precipitation stops.
Recommendations
3
- Do not climb today or in the next few days — the gritstone is deeply saturated and needs an extended dry period before it is safe.
- Monitor the forecast for a sustained dry window of at least 48–72 hours after the last rain before considering a visit.
- When you do visit after drying, check the base of the Calf boulder and lower walls for residual dampness as a reliable indicator of internal moisture.
Do Not Climb
92%
10 days ago
Ilkley Cow and Calf has received nearly 32mm of rain over the past week across multiple events, with the most recent rainfall today (0.2mm) and a significant 6.1mm event just yesterday. The rock is almost certainly saturated internally despite the exposed S/SW aspect, and the forecast shows continued rain every day for the next five days — there is no viable drying window.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks can hold seepage at their bases and in horizontal breaks for days after heavy rain, even when upper faces appear dry.
- The S/SW exposed aspect and open moorland setting normally aid drying, but high humidity (83% average over the past week) and persistent cloud cover are negating these advantages.
- Multiple rain events over the past week (June 1–7) have kept the rock in a near-continuously wetted state, preventing any meaningful drying between showers.
- At 260m altitude, temperatures have been below seasonal averages (13°C mean), further slowing evaporative drying of the gritstone.
Warnings
2
- The gritstone is almost certainly deeply saturated — surface-dry appearance is misleading and holds are at high risk of breakage.
- Climbing on wet gritstone causes permanent, irreversible damage to routes; please respect the well-established local ethic of not climbing on damp rock.
Reasoning
With 31.8mm of rain spread across six of the last seven days and humidity averaging 83%, the gritstone is almost certainly saturated well beyond the critical 1% threshold internally, despite any surface drying between showers.
Although the exposed S/SW aspect and moderate winds (19–31 km/h) would normally promote drying, there has been no consecutive dry period longer than a single day since June 1st, meaning each brief drying interval has been interrupted by fresh wetting.
At current saturation levels, gritstone holds are at significant risk of breakage — compressive strength loss of 10–50% is expected, and repeated wet-dry cycling accelerates grain loosening and surface erosion.
Early June should offer good drying conditions, but this unseasonably wet and cool spell with below-average temperatures and above-average humidity is behaving more like an autumn pattern.
Contributing Factors
6
31.8mm across six rain events in the past seven days has kept the rock in a near-continuously saturated state with no meaningful drying window.
Average humidity of 83% over the past week severely limits evaporative drying, even with good wind exposure.
Zero consecutive dry days means the rock has had no opportunity to begin the 48–72+ hour drying process required after heavy cumulative rainfall.
The south/south-west facing open moorland setting and strong winds (25+ km/h) would normally promote rapid drying, but cannot overcome the frequency of re-wetting.
Mean temperature of 13°C is below the seasonal average for early June, slowing evaporative processes.
Rain is forecast every day from June 8–12, adding a further 18.5mm and eliminating any near-term drying opportunity.
Recommendations
3
- Do not climb at Cow and Calf until there have been at least 48–72 hours of continuous dry weather with humidity below 70% — this is unlikely before mid-June at the earliest.
- Monitor conditions after June 13th, which is the first forecast dry day; even then, check for seepage at the base of the Calf boulder and in horizontal breaks before climbing.
- Consider non-porous alternatives such as limestone venues in the Yorkshire Dales if you need a climbing fix this week.
Do Not Climb
93%
11 days ago
The rock is almost certainly saturated after a prolonged wet spell culminating in 11.1mm of rain today. Over 36mm has fallen in the last 7 days with no meaningful dry period, and the forecast offers no sustained drying window for the coming week.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks are large, porous gritstone masses that absorb significant water during prolonged wet spells — even the south-facing aspects will retain internal moisture after this much cumulative rainfall.
- Seepage and weeping can persist on the lower sections of the Calf and surrounding buttresses for days after heavy rain, particularly around horizontal break lines and the base.
- The exposed moorland setting means strong winds will aid surface drying, but with humidity consistently above 80% and repeated rain, wind alone cannot overcome the moisture recharge.
- The easily accessible car park and popularity of the venue may tempt casual visitors to climb in marginal conditions — please resist and set a good example for crag stewardship.
Warnings
3
- The rock is saturated and structurally compromised — climbing now risks permanent hold breakage and route damage on irreplaceable gritstone.
- Surface drying between showers can be deceptive; the interior of the rock will remain wet for days after the rain stops.
- The forecast shows no dry window in the next 5 days — do not plan climbing trips to this venue this week.
Reasoning
The rock is almost certainly saturated internally: 36.9mm over the past 7 days with 11.1mm today alone and no consecutive dry days means the gritstone has had no opportunity to shed its absorbed water.
Despite the south/south-west aspect and exposed position, the persistent rain every 1–2 days, high humidity (83% average), and moderate temperatures (~13°C) mean any surface drying between showers has been immediately reversed by the next rainfall event.
At current saturation levels, gritstone compressive strength is likely reduced by 30–50%, making hold breakage and surface granulation a serious risk — climbing now would cause permanent damage to routes.
Early June should offer improving conditions, but this spell of unsettled Atlantic weather has kept temperatures below seasonal averages and humidity very high, negating the usual summer drying advantage.
Contributing Factors
7
Over 36mm in the last 7 days with rain on 6 of the last 7 days has kept the rock in a near-continuously wet state.
Today's 11.1mm is the heaviest single-day total in the recent spell, resetting any drying progress to zero.
Average humidity of 83% over the past week and 89% today severely limits evaporative drying even between showers.
The next 5 days show rain on every day (1.0–7.5mm), meaning the rock will receive further moisture before any drying can begin.
The south/south-west aspect and exposed moorland position would normally accelerate drying, but this advantage is overwhelmed by the persistent wet weather.
Sustained winds of 21–31 km/h will help move moist air from the rock surface, but cannot overcome continuous rainfall and high humidity.
Temperatures of 13–15°C are below seasonal averages for June, slowing evaporative drying.
Recommendations
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- Do not climb at Cow and Calf until there have been at least 48–72 hours of continuous dry weather with humidity dropping below 70%.
- Monitor forecasts beyond the current 5-day window — the earliest realistic opportunity may not arrive until mid-June if the unsettled pattern persists.
- If visiting the area, enjoy the walks on Ilkley Moor but leave the rock alone; check UKClimbing forums or local social media for condition updates before planning a session.
Climbing Outlook